FREQUENCY ADAPTIVE REPETITIVE CONTROL FOR WIND POWER APPLICATIONS USING GRID CONNECTED INVERTER

Abstract

This paper presents a novel repetitive control for alternative energy generation systems (WPGS), which achieves best performance in steady-state conditions due to a variable sampling /switching amount technique. The main objective of VSPT is to get an range| number} number of samples per grid amount, which solves the main drawback of RC, i.e., the loss of rejection to periodic disturbances due to grid frequency drift. The sampling/switching frequency is adjusted with a variable sampling period filter phase-locked loop, which additionally adds lustiness to the system due to its inherent tolerance to grid voltage Distortion and unbalances, and events such as frequency steps and faults. The control subsystems are represented, designed, and verified experimentally in a 10-kW WPGS.    The results obtained prove the accuracy of the proposed management even beneath severe disturbances, typical in grids with high WPGS penetration, providing ancillary functions to enhance reliableness and cut back operational prices.